Umbrella stand



FIG. 1 is a perspective view of the umbrella stand;

FIG. 2 is a front view of the umbrella stand, the rear view being a mirror image thereof;

FIG. 3 is a left side view of the umbrella stand;

FIG. 4 is a right side view of the umbrella stand;

FIG. 5 a top view of the umbrella stand; and,

FIG. 6 is a bottom view of the umbrella stand.

The broken lines in the drawings depict portions of the article that form no part of the claimed design. 

CLAIM The ornamental design for an umbrella stand, as shown and described. 